NASA's Plan to Give the Moon a Moon
It sounds almost like a late '90s sci-fi flick: NASA sends a spacecraft to an asteroid, plucks a bou...
Published on: Mar 3, 2016
Transcripts - NASA's Plan to Give the Moon a Moon
NASA's Plan to Give the Moon a Moon
It sounds almost like a late '90s sci-fi flick: NASA sends a spacecraft to an asteroid, plucks a boulder
off its surface with a robotic claw, and brings it back in orbit around the moon. Then, brave
astronaut heroes go and study the space rock up close--and bring samples back to Earth.
Except it's not a movie: That's the real-life idea for the Asteroid Redirect Mission, which NASA
announced today. Other than simply being an awesome space version of the claw arcade game (you
know you really wanted that stuffed Pikachu), the mission will let NASA test technology and practice
techniques needed for going to Mars.
The mission, which will cost up to $1.25 billion, is slated to launch in December 2020. It will take
about two years to reach the asteroid (the most likely candidate is a quarter-mile-wide rock called
2008 EV5). The spacecraft will spend up to 400 days there, looking for a good boulder. After picking
one--maybe around 13 feet in diameter--it will bring the rock over to the moon. In 2025, astronauts
will fly NASA's still-to-be-built Orion to dock with the asteroid-carrying spacecraft and study the rock
Although the mission would certainly give scientists an up-close opportunity to look at an asteroid,
its main purpose is as a testing ground for a Mars mission. The spacecraft will test a solar electronic
propulsion system, which uses the power from solar panels to pump out charged particles to provide
thrust. It's slower than conventional rockets, but a lot more efficient. You can't lug a lot of rocket
fuel to Mars.
Overall, the mission gives NASA a chance at practicing precise navigation and maneuvering
techniques that they'll need to master for a Mars mission. Such a trip will also require a lot more
cargo, so grabbing and maneuvering a big space rock is good practice. Entering lunar orbit and
docking with another spacecraft would also be helpful, as the orbit might be a place for a deep-space
habitat, a rendezvous point for astronauts to pick up cargo or stop on their way to Mars.
And--you knew this part was coming, Armageddon fans--the mission might teach NASA something
about preventing an asteroid from striking Earth. After grabbing the boulder, the spacecraft will
orbit the asteroid. With the added heft from the rock, the spacecraft's extra gravity would nudge the
asteroid, creating a slight change in trajectory that NASA could measure from Earth. "We're not
talking about a large deflection here," says Robert Lightfoot, an associate administrator at NASA.
But the idea is that a similar technique could push a threatening asteroid off a collision course with
NASA chose this mission concept over one that would've bagged an entire asteroid. In that plan, the
spacecraft would've captured the space rock by enclosing it in a giant, flexible container. The claw
concept won out because its rendezvous and soft-landing on the asteroid will allow NASA to test and
practice more capabilities in preparation for a Mars mission, Lightfoot says. The claw would've also
given more chances at grabbing a space rock, whereas it was all or nothing with the bag idea. "It's a
one-shot deal," he says. "It is what it is when we get there." But the claw concept offers some
choices. "I've got three to five opportunities to pull one of the boulders off," he says. Not bad odds.
Better than winning that Pikachu.